This invention relates to aqueous piroxicam solutions useful in the treatment of inflammations of the eye such as allergic conjunctivitis, edemas, acute uveitis, ocular trauma, scleritis and keratoconjunctivitis.
Piroxicam, the chemical name of which is N-(2-pyridyl)-2-methyl-4-hydroxy-2H-1,2-benzothiazine-3-carboxamide 1,1-dioxide, is a nonsteroidal anti-inflammatory agent. It is described and claimed in U.S. Pat. No. 3,591,584.
Several piroxicam containing pharmaceutical compositions for uses other than ophthalmic administration are known. U.S. Pat. No. 4,688,053 refers to injectable solutions containing piroxicam. U.S. Pat. No. 4,678,666 refers to piroxicam containing gels for dermatological administration. Japanese Patent Application Disclosure 62-142116 refers to piroxicam containing suppositories.
Aqueous piroxicam suspensions for ophthalmic use are also known. Belgian patent 899,587 refers to an anti-inflammatory eye lotion that is a suspension of piroxicam in an aqueous, sterile, hypertonic solution.
In the ophthalmic compositions of the present invention, piroxicam, the active ingredient, is dissolved in an aqueous solution, facilitating administration of the drug, accuracy in dosing and patient toleration. The fact that the active ingredient is dissolved in solution also prevents blurring and causes such compositions to be faster acting than suspensions of piroxicam.
The aqueous piroxicam solutions of the present invention also exhibit substantially greater stability than the aqueous piroxicam suspensions. They need not be nitrogen purged during preparation and storage. The stability inherent in the novel solutions of this invention may be further enhanced by packaging them in containers capable of blocking transmission of light having a wavelength in the range from about 290 nm to about 550 nm.